1. Field of the Invention
The invention relates to a clamping mechanism in a vise jaw accessory system for attaching and releasing vise accessories, such as positioning plates. More particularly, the invention relates to a clamping mechanism for a vise jaw accessory system for attaching and releasing accessories to and from a vise while maintaining the positional accuracy of the accessory in three directions relative to a horizontal datum surface and vertical longitudinal and lateral datum surfaces. The clamping mechanism combines a locking screw arrangement with a spring biased detent arrangement for providing a biasing pressure to hold a workpiece such as a positioning plate, and a locking pressure to disable the bias pressure and lock the workpiece in position.
2. Discussion of Related Art
U.S. Pat. No. 4,923,186 (the disclosure of which is herein incorporated by reference) discloses a mechanism for lateral insertion of a positioning plate into a recess within a vise jaw. That construction is adequate for many purposes, but often times greater positional accuracy is desired in the lateral direction, particularly in "mirror image" situations when two positioning plates face each other on opposing jaws and must be aligned laterally so as not to skew the work piece held between the plates during machining. Further, insufficient space may exist for lateral insertion of the positioning plates. That construction also provides separate mechanisms such as a spring-biased detent for providing a bias pressure against the positioning plate, and a set screw for providing a locking pressure on the positioning plate.